
/*
 * Copyright 2002-2022 the original author or authors.
 *
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 *      https://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */
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 *版权所有2002-2022原作者。
 *
 *根据Apache许可证2.0版（“许可证”）获得许可；
 *除非符合许可证，否则不得使用此文件。
 *您可以在以下地址获取许可证副本：
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 *除非适用法律要求或书面同意，软件
 *根据许可证分发的内容是按“原样”分发的，
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package org.springframework.beans.factory.support;

import java.lang.reflect.Constructor;
import java.lang.reflect.Method;

import org.springframework.beans.BeansException;
import org.springframework.beans.factory.BeanFactory;
import org.springframework.lang.Nullable;

/**
 * Interface responsible for creating instances corresponding to a root bean definition.
 *
 * <p>This is pulled out into a strategy as various approaches are possible,
 * including using CGLIB to create subclasses on the fly to support Method Injection.
 *
 * @author Rod Johnson
 * @author Juergen Hoeller
 * @since 1.1
 */
/**
 *负责创建与根bean定义对应的实例的接口。
 *
 *<p>这被引入一种策略，因为各种方法都是可能的，
 *包括使用CGLIB动态创建子类以支持方法注入。
 *
 *@作者Rod Johnson
 *@作者Juergen Hoeller
 *@自1.1
 */
public interface InstantiationStrategy {

	/**
	 * Return an instance of the bean with the given name in this factory.
	 * @param bd the bean definition
	 * @param beanName the name of the bean when it is created in this context.
	 * The name can be {@code null} if we are autowiring a bean which doesn't
	 * belong to the factory.
	 * @param owner the owning BeanFactory
	 * @return a bean instance for this bean definition
	 * @throws BeansException if the instantiation attempt failed
	 */
	/**
	 *返回此工厂中具有给定名称的bean实例。
	 *@param bd bean定义
	 *@param beanName在此上下文中创建bean时的名称。
	 *如果我们正在自动连接一个没有
	 *属于工厂。
	 *@param所有者拥有的BeanFactory
	 *@return此bean定义的bean实例
	 *如果实例化尝试失败，@throws BeansException
	 */
	Object instantiate(RootBeanDefinition bd, @Nullable String beanName, BeanFactory owner)
			throws BeansException;

	/**
	 * Return an instance of the bean with the given name in this factory,
	 * creating it via the given constructor.
	 * @param bd the bean definition
	 * @param beanName the name of the bean when it is created in this context.
	 * The name can be {@code null} if we are autowiring a bean which doesn't
	 * belong to the factory.
	 * @param owner the owning BeanFactory
	 * @param ctor the constructor to use
	 * @param args the constructor arguments to apply
	 * @return a bean instance for this bean definition
	 * @throws BeansException if the instantiation attempt failed
	 */
	/**
	 *返回此工厂中具有给定名称的bean实例，
	 *通过给定的构造函数创建它。
	 *@param bd bean定义
	 *@param beanName在此上下文中创建bean时的名称。
	 *如果我们正在自动连接一个没有
	 *属于工厂。
	 *@param所有者拥有的BeanFactory
	 *@param ctor要使用的构造函数
	 *@param args要应用的构造函数参数
	 *@return此bean定义的bean实例
	 *如果实例化尝试失败，@throws BeansException
	 */
	Object instantiate(RootBeanDefinition bd, @Nullable String beanName, BeanFactory owner,
			Constructor<?> ctor, Object... args) throws BeansException;

	/**
	 * Return an instance of the bean with the given name in this factory,
	 * creating it via the given factory method.
	 * @param bd the bean definition
	 * @param beanName the name of the bean when it is created in this context.
	 * The name can be {@code null} if we are autowiring a bean which doesn't
	 * belong to the factory.
	 * @param owner the owning BeanFactory
	 * @param factoryBean the factory bean instance to call the factory method on,
	 * or {@code null} in case of a static factory method
	 * @param factoryMethod the factory method to use
	 * @param args the factory method arguments to apply
	 * @return a bean instance for this bean definition
	 * @throws BeansException if the instantiation attempt failed
	 */
	/**
	 *返回此工厂中具有给定名称的bean实例，
	 *通过给定的工厂方法创建它。
	 *@param bd bean定义
	 *@param beanName在此上下文中创建bean时的名称。
	 *如果我们正在自动连接一个没有
	 *属于工厂。
	 *@param所有者拥有的BeanFactory
	 *@param factoryBean调用工厂方法的工厂bean实例，
	 *或｛@code null｝（如果是静态工厂方法）
	 *@param factoryMethod要使用的工厂方法
	 *@param args要应用的工厂方法参数
	 *@return此bean定义的bean实例
	 *如果实例化尝试失败，@throws BeansException
	 */
	Object instantiate(RootBeanDefinition bd, @Nullable String beanName, BeanFactory owner,
			@Nullable Object factoryBean, Method factoryMethod, Object... args)
			throws BeansException;

	/**
	 * Determine the actual class for the given bean definition, as instantiated at runtime.
	 * @since 6.0
	 */
	/**
	 *确定在运行时实例化的给定bean定义的实际类。
	 *@自6.0起
	 */
	default Class<?> getActualBeanClass(RootBeanDefinition bd, @Nullable String beanName, BeanFactory owner) {
		return bd.getBeanClass();
	}

}
